Protective device for anti-aircraft installations and nuclear power stations

ABSTRACT

A protective door device for anti-aircraft installations and nuclear power stations has a door opening in a wall preferably designed as a concrete wall. The opening is surrounded on all sides by the wall and can be closed by means of a protective door which overlaps the wall. The protective door has a central lock and a bowl-shaped metal door leaf reinforced by ribs, from which one-piece support arms project. Two bearing bolts on which two door hinges are mounted are inserted in the wall near the door opening and pockets for adjustable engagement of lock bails of the central lock are arranged in the intrados of the door opening.

The invention pertains to a protective door device for anti-aircraftinstallations and nuclear power stations. It has a door opening in awall preferably designed as a concrete wall and a protective, closeabledoor that overlaps the wall.

In the event of an atomic accident or explosion there occurs in additionto such immediate effects as a pressure wave and its subsequent suctionwave the release of radio-active rays. These remain active for a longtime. If, for example, atomic bombs with supplemental devices--that is,plutonium bombs--are detonated, poisonous gases, which are generallyradio-active, are also released.

In the event of nuclear catastrophies, therefore, or if tactical nuclearweapons are employed, all protective devices must on the one hand besecure against all pressure waves and, on the other hand, they muststill seal to such a degree that the protective device is impervious toall subsequent effects but especially those which derive fromradio-active material. All this makes truly extraordinary demands on aprotective door device, but these demands are, in general, not met bydoors currently in service. A protective door device should be capableof withstanding a pressure wave of 10 bar (as a reflected pressure wave)and continue to provide total sealing, and it should also survive thesubsequent suction wave and continue to seal properly. These twopressure waves, which follow rapidly one after the other and, acting inopposite directions, cause pressure and then suction, place high demandson the mechanical rigidity.

Proceeding from these considerations it is the purpose of the inventionto create for anti-aircraft installations and nuclear power stations aprotective door which will continue to seal while withstanding both areflected pressure wave of 10 bar and the subsequent suction wave andwhich can be produced at a reasonable price.

This problem is solved by means of a protective device for anti-aircraftinstallations and nuclear power stations. It has a door opening in awall preferably designed as a concrete wall. The opening is surroundedon all sides by the wall and can be closed by means of a protective doorwhich overlaps the wall. The protective door has a central lock and abowl-shaped metal door insert which is reinforced by ribs, and from thelongitudinal edges of the door one-piece support arms project. Twobearing bolts on which two door hinges are mounted are inserted in thewall near the door opening, and pockets for adjustable engagement oflock bails of the central lock are arranged in the door jambs.

The door insert, made of aluminum or steel, is cast in one piece bycasting or by casting under pressure. It acquires its ability towithstand the reflected pressure wave though on the one hand the convexshape that it presents to this pressure wave--the door is bowlshaped--and, on the other, through the reinforcing ribs. No frame isused. Rather, the door is hung on hinges which are set directly in thewall by means of two bearing bolts. The door opening is surrounded onall sides by the wall. Thus it does not, as is the case with a door to aroom, border on a floor or on another surface. The door opening ispreferably round--at least it should not be square. Especiallyrecommended is an oval shape--and by oval should be understood inaddition to egg-shaped a design that is formed by two semicircles andthe straight lines which join them. (cf. the oval in a stadium).

When the pressure wave is felt the door leaf is pressed against theoutside wall around the door opening. During the following suction wavethe door leaf is held in place by the lock bails. Moreover, as the gripof the lock bails in the pockets can be adjusted, a good seal can bemaintained even while the suction wave can be felt. In this respect itis especially advantageous if the contact areas of the lock bails areheld elastically in place in the pockets. This is achieved preferably bya spring which loads the pertinent ends of the lock bails in a directionthat is transverse to the main surface of the door leaf. A loading indirections that are transverse to the longitudinal axis of the lockbails is advantageous.

The door leaf is preferably oval, at least it should be symmetrical whenturned through 180 degrees. In this way just one type of door needs tobe manufactured, and the hinges can be affixed on either the left or theright side.

The door leaf has preferably an outer surface that is smooth orspherically or spherically-cylindrically rounded. This outer surfaceshould form at the edges an overlapping area, and the door leaf is toexceed the size of the door opening in the wall by the equivalent ofthis overlapping area. The seal is attached to the door on thisoverlapping area and placed so that it faces the wall. Directly besidethe seal and projecting away from the inside of the door there ismounted a rotatable rib in the form of a short supporting sleeve. Theouter dimensions of this rib are to be just minimally shorter than theinner dimensions of the door opening. On the free edge of theoverlapping area a reinforcing edge projects outward. This reinforcingedge supports the overlapping area in such a way that it is not shearedoff during the shock wave. Such an arrangement of the two flangestogether with the enclosed seal is essentially "z" shaped, and it hasproved to be especially advantageous. It provides the door leaf with themechanical rigidity that is necessary if it is to withstand successfullythe shock wave.

From the rib that completely encircles the door leaf on its outer edgewhole systems of ribs cover the total inner surface of the door insert.These meet and branch out from a veritable host of nubs. In muchsimplified terms, the reinforcing that is achieved by these ribs can beexpressed thus: longitudinally three parallel ribs transverse the centresection of the door insert from the top to the bottom. These ribsintersect and join up with three ribs which, equidistant from oneanother, cross the door leaf from one side to the other. Between thisset of three longitudinal ribs and the outer rib there is mounted oneither side another, straight rib. Thus, the door is reinforcedlongitudinally by five parallel ribs. Transversely, three additionalribs are mounted on each side between the three center ribs and theoutside rib. Thus transversely the door is reinforced by no fewer thaneleven ribs. In addition, the sectors which are formed by theintersection of each of the three inner longitudinal and transverse ribsare reinforced by diagonal ribs.

The support arms are mounted in duplicate and are V-shaped in the areaof the door hinges. They are attached to the outside of the door.

Further characteristics and advantages of the invention will be evidentfrom both the remaining claims and the following description of onepossible version of the door, it being understood that the versiondiscussed does not limit in any way the scope of the claims sought. Thisversion is described more closely with reference to the drawings.

Of these:

FIG. 1 the inside view of the door leaf of the protective door device;

FIG. 2 a horizontal cross section through a protective door device witha door leaf constructed according to FIG. 1;

FIG. 3 Detail III of FIG. 2 enlarged;

FIG. 4 a plan view on to the outside surface of a protective deviceconstructed in accord with the idea and details of this invention.

The protective door device constructed according to these drawingsconsists of a protective door (20), a door opening (24) that is cited ina wall (22), two hinging arrangements each with support arms (28) andhinges (30) as well as a central locking device (32) to which belongpockets (34) in the door jambs (24).

The protective door consists essentially of an oval shaped door leaf(36). The surface of this door, which is shaped like a shield andmounted so as to present a convex surface to the pressure side (38),overlaps the door opening (24) all around when in the closed position(shown in the drawings). Around its outer rim, the door leaf has an edgewhich is essentially flat, approximately 25 to 50 mm thick andreinforced inwardly by a system of ribbing that is now described ingreater detail: A net of ribs which follow the main directions of thedoor (36) transverses it through its midpoint (40). To the left andright of this middle point additional ribs spaced approximately 6 cm.apart are mounted. Thus a three-ribbed cross, which in the vicinity ofthe middle point (40) is reinforced by further diagonal ribs, is formed.The four sectors thus formed are reinforced by further ribs. These ribsare joined to an encircling rib (42) that completely surrounds theoval-shaped door leaf. All the ribs are manufactured in one piece on thedoor leaf (36) and merge without a break into the ribs that theyintersect or are joined to. The external edge of the rib that encirclesthe door leaf (42) defines for all practical terms the door opening (24)which is but minimally larger than the external measurement of theencircling rib (42). The decisive factor is that the door leaf (36) isto cover completely the door opening (24) as is especially evident fromFIG. 4. A surface (44) is cited there at a distance below the protectivedoor (20) and thus at some distance from the door opening (24). Inconsequence, a step must be surmounted when passing in or out of theprotective door. Only if the door opening is completely surrounded (bythe wall) can a proper seal to all sections of the edges of the door beachieved. The enveloping rib (42) and some of the inner ribs project asfar into the internal surface (protected side 46) of the door that theirfree ends are on the one plane. All other ribs are shorter and endbefore this plane. If the door leaf is approximately 90×130 cm the totalheight of the enveloping rib (42) is approximately 20 cm, and thisrib--like all other ribs--narrows at its free end to approximately 10mm.

A total of four support arms (28) are mounted on the pressure side (38).These begin on the middle line of the door and run in pairs to thehinges (30) forming a "V", the axis of each being cited approximately 15cm. from the adjoining edge of the door leaf (36). Each of the pairedsupport arms (28) ends above and below a bearing bolt (48) that canreceive a hinge bolt (50). In each pair of support arms the arm nearestthe middle point (40) runs straight and at an angle of 90 degrees to thelongitudinal axis of the door. Thus it locks into what is approximatelythe center of gravity of the pertinent, which is to say upper or lower,door-half. The second support arm begins a few centimeters above--or,respectively, below--the highest--or the lowest--point of the envelopingrib (42) but on the opposite side.

The door leaf (36) together with its ribs and the total of 4 supportarms is manufactured (cast) in one piece from, for example, GAISi orsteel.

On the outermost edge of the outside of the door leaf (36) a reinforcingedge (52) projects at right angles to the main surface of the door leaf(36). This edge affords that section of the door leaf which projectsbeyond the enveloping rib (42) such rigidity that this peripheral areacan not be sheared off when pressure is exerted on the pressure side(38). Below this peripheral area to which reference has just been madethere is a seal (54) (details evident from FIG. 3). From this Figure itwill be evident that the seal (54) consists essentially of a strip ofelastic material. When the door is closed the region 56 first comes incontact with the outer surface of the wall (22): this is achieved bymeans of the angular section of the inner surface of the overlappingarea.

A sealing shaft (58) which can transverse a distance of approximately 25cm and which is sealed by O-rings so as to be impervious to gas passesthrough the center point (40). It is mounted transversely to the doorleaf (36). This shaft forms on the pressure side (38) a squareprotuberance on which an activating lever or wheel can be mounted. Adevice for activating the shaft is mounted permanently on the end of theshaft that is on the inside. The sealing shaft (58) is linked in thefamiliar way with eccentric connections (60) to which locking bails areattached. Each of these is mounted in bearings (62) which are mounted onthe free ends of ribs. Each free end of a locking bail is aligned to oneof the pockets (34). In each of the pockets there is mountedtransversely to the entry/exit axis of the door opening a pair ofmoveable, adjustable sealing blocks (64), each sealing block having aslanted face so that the free end of the sealing rod (64) can be themore easily inserted. The sealing blocks (64) are adjusted in such a waythat when the locking bails (66) are fully extended (see FIG. 2) theseal (54) is pressed against the wall (22) around the totalcircumference as is shown, for example, in FIG. 3. By means of theadjustability of the sealing blocks (64) it is possible to compensatefor unevenness on the surface of the wall (22) as well as discrepanciesin the dimensions of the door leaf (36).

The pockets (34) are constructed as follows: A box (70) which is made ofsteel plate and which has an opening for the insertion of the lockingbails (66) is constructed in the wall (22) and firmly embedded in it.Two sealing blocks (64) are mounted in each of these boxes. These blocksare adjustable transversely to the main surface of the door leaf (36)and at the same time rendered elastic by means of springs (pressurecoil-springs: 72) which stress the sealing blocks in this direction.Adjustment is achieved in this way: The sealing block that faces thedoor leaf (36) presses the free end of the lock bails (66) against theprotective side (46), thereby forcing the protective seal (54) againstthe outside surface of the wall (22). When a shock wave is felt the freeend of the lock bails (66) can move with the pressure, but it will nothe sheared off. In this way the protective door is able to withstandenormous dynamic stresses. In another version the springs (72) are notemployed. In their place the free end of each of the lock bails (66) isjoined elastically to the main section of the lock bail (66), therebyensuring that the free ends are not sheared off by a pressure wave.

The bearing bolts (48) are mounted in supporting rods which are citedoutside the actual door opening (24) and which are set in the wall (22).These supporting rods are incorporated when the concrete body of thewall is cast, and their inner diameter exceeds by several millimetersthe external diameter of the bearing bolts (48) so that the door can beadjusted. The bearing bolts (48) are threaded on the protected side (46)and appropriately sealed (e.g. by a silicon mass or O-rings) so as torender the inside impervious to gas. The axial position of the bearingbolts can be adjusted by inserting a thinner or thicker washer in placeof the washer (74) that is mounted between the head of the bearing boltthat accepts the hinge bolt (50) and the outer surface of the wall (22).

What is claimed is:
 1. A protective door device for anti-aircraftinstallations and nuclear power stations comprising a door opening in awall that is constructed of concrete, the door opening exhibiting a doorjamb in which pockets for adjustable elastic engagement of lock bailsare arranged; two bearing bolts which are inserted near the door openingand on which two door hinges are mounted; and a closeable, protectivedoor overlapping said door opening having a central lock and areinforced metal door leaf exhibiting a bowl-shaped outer surface and aninner surface which door leaf comprises the said lock bails, from whichdoor leaf support arms project that carry the said door hinges, areinforcing ridge protrudes from the outer edge of the bowl-shaped outersurface of the door leaf transverse to the main plane of the door leafand completely encircles said door leaf, and a reinforcing rib isarranged on the inner side of the door leaf, which rib completelyencircles the door leaf, the external measurements of this rib areminimally smaller than the inner measurements of the door opening. 2.The protective door device according to claim 1, wherein the door leafis, with the exception of some reinforcing ribs, essentially symmetricalwhen turned through 180 degrees.
 3. The protective door device accordingto claim 1, wherein a seal is mounted outside of the rib completelyencircling the door leaf and on the inner surface of the door leaf wherethe door leaf overlaps the door opening.
 4. The protective door deviceaccording to claim 3, wherein seal exhibits a sealing surface, whichfirst makes contact with the door opening when the door is closed. 5.The protective door device according to claim 1, wherein the ribcompletely encircling the door leaf and further ribs, ends in a planethat runs parallel to the main plane of the door leaf.
 6. The protectivedoor device according to claim 1, wherein a plate is mounted on theinner surface of the door leaf, whereby hollow spaces are formed betweenthe door leaf and said plate.
 7. The protective door device according toclaim 1, wherein in each of the pockets a pair of locking blocks withdiagonal inlet are mounted, which locking blocks are adjustabletransversely to the main plane of the door opening.
 8. The protectivedoor device according to claim 1, wherein next to the door opening twosupporting rods are firmly embedded.